Grate inlet



E- R. ROWLAND GRATE INLET May 14, 1963 2 Sheets-Sheet 1 Filed April 4, 1960 May 14, 1963 E. R. ROWLAND GRATE INLET 2 Sheets-Sheet 2 Filed April 4, 1960 3,089,396 GPATE INLET Eugene R. Rowland, Kirkwood, M0. (16 N. (lentral Ave, (Ilayton 5, Mo.) Filed Apr. 4, 196%, Ser. No. 19,813 3 (Iiairns. (81. 94-311) This invention relates to grate inlets for streets and highways, and more particularly to a self-cleaning inlet of this class.

Among the several objects of the invention may be noted the provision of an improved grate inlet of the class described for storm water removal from streets and highways which is effectiveiy self-cleaning so as to avoid obstruction thereof by leaves or other debris, the construction of the grate being such that leaves and other debris are flushed through the inlet and down into the storm water drain; the provision of a grate inlet such as described which has adequate hydraulic capacity for draining off storm water even during periods of high run-off; the provision of a grate inlet such as described which is economical to make and install and which requires minimum maintenance; the provision of a grate inlet such as described which may be of such weight and which may be installed in such manner that it may be readily removed from the pavement for access to the drain, or replacement of a damaged inlet, or for installing a blank plate in place the provision of a grate inlet such as described which is so constructed as to minimize the collection of ice or snow thereon, the top surface of the inlet being such as to avoid hanging up of chunks of ice or frozen snow, and discharge of snow and chunks of ice into the drain being facilitated; the provision of a grate inlet such as described which may be used at various types of curbs, including lip type curbes and vertical curbs, or even in other locations where the contour is such as to direct storm water towards the inlet; and the provision of a grate inlet such as described which does not offer any hazard to trafiic and which presents an improved esthetic appearance.

A principal feature of the grate inlet of this invention is that it comprises a plurality of grate bars which extend at an angle with respect to the direction of flow of storm water to the inlet, these grate bars angling toward one side of the inlet in downstream direction, being spaced apart, and inclined downwardly in downstream direction to provide passages between the grate bars which are inclined downwardly in downstream direction. The grate bars provide a spillway conformation and storm water flows smoothly over the bars and down through the stated passages into the drain, thereby minimizing hydraulic jump, air pockets, cavitation and turbulence, with the resuit that the flow of water through the inlet is speeded up in comparison with prior grate inlets, and the hydraulic capacity of the inlet is thereby greater. With the bars at an angle with respect to the direction of flow, the vector of the force of the water in the direction of the bars is utilized to flush debris off to one side and the inlet is effectively sel f-cleansing and practically clog-proof. A further feature of the grate inlet of this invention is that a clear opening maybe provided at the stated one side of the inlet,

* any debris that does not pass through the grate bars being moved along the top of the inlet by the stated force vector of the water and flushed down through the clear openmg.

Other objects and features will be in part apparent and in part pointed out hereinafter.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

Patented May 14, 1963 FIG. 1 is a perspective view showing a grate inlet of this invention set into a pavement;

FIG. 2 is a plan view of FIG. 1;

FIGS. 3, 4 and 5 are enlarged cross sections taken on lines 33, 4-4 and 55, respectively, of FIG. 2;

FIG. 6 is a cross section taken on line 66 of FIG. 5;

FIG. 7 is an enlarged vertical section taken on line 7--7 of BIG. 2;

FIGS. 8 and 9 are vertical sections taken on lines 88 and 9-9, respectively, of FIG. 7; and

FIG. 10 is an enlarged vertical section taken substantially on line 1tl10 of FIG. 1.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to the drawings, FIGS. 1 and 2 show a grate inlet 1 of this invention as it appears when placed in street or highway pavement 3 in gutter 5 of the pavement adjacent a curb 7. The grate inlet is received in a recess 9 in the pavement substantially flush with the pavement at the entrance to a drain 11 (see FIG. 5) such as a storm sewer drain. Recess 9 is larger than drain 11 so as to provide a shoulder 13 (see FIG. 4) for supporting the grate inlet. This shoulder extends around the bottom of recess 9 except at the curb side of the recess. As illustrated in FIG. 1, the grade of the pavement is such that storm water flows down gutter 5 to inlet 1 from the left, as indicated by the arrow A in FIG. 1.

In accordance with this invention, the grate inlet 1 comprises a plurality of grate bars 15 which extend toward one side of the inlet (the side toward the curb 7) at an angle of approximately 45 with respect to the direction of flow of storm water to the inlet, and angling toward this side of the inlet in downstream direction. The grate bars 15 are spaced apart and inclined downwardly in downstream direction, preferably at an angle of less than 45 to the horizontal, thereby to provide passages 17 (see FIG. 3) between the bars which are inclined downwardly in downstream direction.

As shown best in FIG. 3, each grate bar 15 is of streamline form in cross section, being slightly curved throughout its width and having an upper featheredge 19. The lower surface of each grate bar, which is concave, is designated 21 and the upper surface of each grate bar, which is convex, is designated 23. The upper portion of upper surface 23 converges toward lower surface 21 as indicated at 25 to provide the upper featheredge 19. The lower edge 27 of each grate bar is .a full- Width flat edge essentially at right angles to surfaces 21 and 23. Featheredge 19 of each grate bar is its upstream edge, and each grate bar curves downwardly in downstream direction so that passages 17 curve downwardly in downstream direction for free overfall of water around edges 19 and smooth curved spillwaylike diversion of water downward through the passages, thereby avoiding hydraulic jump, air pockets, cavitation and turbulence.

The grate bars 15 are secured as by welding in a frame designated in its entirety by reference character 29. This frame comprises upstream and downstream end members 31 and 33 and a side member 35 (at the side thereof away from curb 7). Each of these members, as shown, may consist of an angle iron having a vertical leg 37 and an inwardly directed horizontal leg 39. End members 31 and 33 extend at right angles to side member 35 from the ends of the latter, being welded thereto. The frame is removably received in recess 9 in the pavement, the horizontal legs 39 of the angle iron frame members 31, 33 and 35 bearing on the aforesaid shoulder 13 at the bottom of recess 9. End members 31 and 33 extend to the curb. The upper edges of the grate bars 15 are substantially coplanar with the upper edges of the assasse end and side members 31, 33 and 35 and the height of the vertical legs 37 of the members 31, 33 and 35 corresponds to the height of recess 9 so that the top surface of the grate inlet is substantially flush with the surface of the pavement.

A supporting beam 41 for grate bars 15 extends between the frame end members 31 and 33 adjacent the curb side of the frame 29 parallel to side bar 35 but spaced inwardly from the curb ends of end members 31 and 33 so as to provide a clear opening 43 between the beam 41 and the face of the curb. The ends of the beam 41 are notched as indicated at 45, thereby providing narrow end extensions 47 of the beam which bear on the horizontal legs 39 of the end angle iron members 31 and 33. As appears in FIGS. and 8, beam 41 is slightly curved in cross section and is inclined downwardly in the direction toward the curb. Its upper edge 49, which is rounded, is located above the horizontal legs of the end angle iron members 31 and 33 and its lower edge 51, which may be bevelled so as to be horizontal, is located substantially below the horizontal legs. Reinforcing plates 53 are welded to the ends of beam 41 and are notched similarly to beam 41 to have extensions 55 which bear on the horizontal legs of the end angle iron members 31 and 33 and which are welded to the latter.

The grate bars 15 are supported on the legs of the angle iron members 31, 33 .and 35 and the beam The latter has notches 57 (see FIG. 6) for receiving end portions of those grate bars 15 which intersect beam 41 at points between the end members 31 and 33. Those grate bars 15 which intersect end plates 53 have notches such as indicated at 59 in FIGS. 8 and 9 accommodating extensions 55 of plates 53 and extensions 47 of beam 41. The grate bars 15 terminate over the beam 41 to provide the clear opening 43. The angle iron members 31, 33 and 35, the grate bars 15, the beam 41 and plates 53 are all welded together to provide a strong unitary construction.

From the above, it will be apparent that storm water flowing down gutter 5 to the grate inlet 1 as indicated by the arrow A in FIG. 1 will flow smoothly over the grate bars 15 and down through passages 17 into the drain 11, the construction being such as to minimize hydraulic jump, air pockets, cavitation and turbulence. As a result, the grate inlet 1 has relatively high capacity in relation to its size for draining olT storm water. With grate bars 15 extending to the clear opening 43 at an angle with respect to the direction of flow of storm water to the grate inlet, and angling toward the clear opening 43 in downstream direction, the force vector of the water in the angled direction of the bars (i.e., at an angle of 45 in downstream direction toward clear opening 43) is utilized to flush any debris that does not pass through passages 17 over to the clear opening 43 and down through the latter into the drain 11. The top surface of the grate inlet is such as to avoid hanging up of chunks of ice or frozen snow thereon, and does not offer any hazard to traffic.

While the grate inlet 1 is herein illustrated as used adjacent a curb (which may be a lip-type curb or a vertical curb), it will be readily understood that it may be used in other locations where the contour is such as to direct storm water to the inlet, the inlet being positioned with grate bars 15 at an angle to the direction of flow of storm water to the inlet, and angling toward one side of the inlet in downstream direction. While a rectangular configuration is shown for the grate inlet, this is not essential.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A grate inlet comprising a frame constituted by a side member, end members extending laterally from the ends of said side member, one of said end members constituting an upstream end member in respect to the direction of flow of storm water to the inlet and the other constituting a downstream end member, and a beam secured to and extending between said end members spaced inwardly from the ends of said end members remote from said side member, a plurality of grate bars secured to and supported by said side and end members and said beam with their upper edges substantially coplanar with the upper edges of said side and end members, said grate bars extending to said beam at an angle with respect to the direction of flow of storm water to the inlet, and angling toward said beam in downstream direction, said grate bars being spaced apart throughout their length a distance greater than their thickness and inclined downwardly in downstream direction thereby to provide passages between the grate bars which are of greater width than the thickness of said bars and which are inclined downwardly in downstream direction for smooth fiow of water therethrough, each grate bar being curved in cross section, having a concave lower surface and a convex upper surface, and curved downwardly in downstream direction, and said grate bars terminating over said beam to provide a. clear opening laterally outward from the respective ends of said grate bars for flushing of debris which does not pass through said passages, each of said grate bars having a relatively thin upper upstream edge.

2. A grate inlet as set forth in claim 1 wherein the grate bars extend at a 45 angle with respect to said side member and beam and are inclined at an angle of less than 45 to the horizontal.

3. A grate inlet comprising a frame constituted by an an angle-section side member having an inwardly directed horizontal lower leg, angle-section end members welded to and extending laterally from the ends of said side member, each having an inwardly directed horizontal lower leg, one of said end members constituting an upstream end member in respect to the direction of flow of storm water to the inlet and the other constituting a downstream end member, and a beam welded to and extending between the horizontal legs of said end members spaced inwardly from the ends of said end members remote from said side member, said beam having its upper edge below the upper edges of said side and end members, a plurailty of grate bars supported by the horizontal legs of said side and end members and said beam with their upper edges substantially coplanar with the upper edges of said side and end members, said grate bars extending to said beam at an angle of approximately 45 with respect to the direction of flow of storm water to the inlet, and angling toward said beam in downstream direction, said grate bars being spaced apart throughout their length a distance greater than their thickness and inclined downwardly in downstream direction at an angle less than 45 to the horizontal thereby to provide passages between the grate bars which are of greater width than the thickness of said bars and which are inclined downwardly in downstream direction for smooth flow of water therethrough, each grate bar having a featheredge at its upstream edge, and said grate bars terminating over said beam to provide a clear opening laterally outward from the respective ends of said grate bars for flushing of debris which does not pass through said passages, each grate bar being curved in cross section, having a concave lower surface and a convex upper surface, and curved downwardly ibn downstream direction, and fitting in a notch in said eam.

References Cited in the file of this patent UNITED STATES PATENTS 1,420,535 Farrell June 20, 1922 (Other references on following page) 5 UNITED STATES PATENTS Keeble Jan. 3, 1928 Wittman Feb. 14, 1928 Shurtleff May 6, 1930 Ladd Feb. 25, 1936 Karrnazin May 31, 1938 Germonprez Nov. 8, 1938 6 Gerrnonprez Apr. 2, 1940 Boericke June 16, 1959 FOREIGN PATENTS Great Britain Oct. 23, 1909 Great Britain Oct. 10, 1929 

1. A GRATE INLET COMPRISING A FRAME CONSTITUTED BY A SIDE MEMBER, END MEMBERS EXTENDING LATERALLY FROM THE ENDS OF SAID SIDE MEMBER, ONE OF SAID END MEMBERS CONSTITUTING AN UPSTREAM END MEMBER IN RESPECT TO THE DIRECTION OF FLOW OF STORM WATER TO THE INLET AND THE OTHER CONSTITUTING A DOWNSTREAM END MEMBER, AND A BEAM SECURED TO AND EXTENDING BETWEEN SAID END MEMBERS SPACED INWARDLY FROM THE ENDS OF SAID END MEMBERS REMOTE FROM SAID SIDE MEMBER, A PLURALITY OF GRATE BARS SECURED TO AND SUPPORTED BY SAID SIDE AND END MEMBERS AND SAID BEAM WITH THEIR UPPER EDGES SUBSTANTIALLY COPLANAR WITH THE UPPER EDGES OF SAID SIDE AND END MEMBERS, SAID GRATE BARS EXTENDING TO SAID BEAM AT AN ANGLE WITH RESPECT TO THE DIRECTION OF FLOW OF STORM WATER TO THE INLET, AND ANGLING TOWARD SAID BEAM IN DOWNSTREAM DIRECTION, SAID GRATE BARS BEING SPACED APART THROUGHOUT THEIR LENGTH A DISTANCE GREATER THAN THEIR THICKNESS AND INCLINED DOWNWARDLY IN DOWNSTREAM DIRECTION THEREBY TO PROVIDE PASSAGES BETWEEN THE GRATE BARS WHICH ARE OF GREATER WIDTH THAN THE THICKNESS OF SAID BARS AND WHICH ARE INCLINED DOWNWARDLY IN DOWNSTREAM DIRECTION FOR SMOOTH FLOW OF WATER THERETHROUGH, EACH GRATE BAR BEING CURVED IN CROSS SECTION; HAVING A CONCAVE LOWER SURFACE AND A CONVEX UPPER SURFACE, AND CURVED DOWNWARDLY IN DOWNSTREAM DIRECTION, AND SAID GRATE BARS TERMINATING OVER SAID BEAM TO PROVIDE A CLEAR OPENING LATERALLY OUTWARD FROM THE RESPECTIVE ENDS OF SAID GRATE BARS FOR FLUSHING OF DEBRIS WHICH DOES NOT PASS THROUGH SAID PASSAGES, EACH OF SAID GRATE BARS HAVING A RELATIVELY THIN UPPER UPSTREAM EDGE. 